Lenticular lenses take the form of a transparent plastic sheet or web. On one side, the sheet or web typically includes an array of identical curved or ribbed surfaces that are formed (e.g., cast, coated, embossed, extruded, or co-extruded) on the front surface of the plastic sheet. The back surface of the lens is typically flat. Each lenticular or individual lens is a section of a long cylinder that focuses on, and extends over, substantially the full length of an underlying image. Other lens shapes or profiles are possible (for instance, elliptical, pyramidal, trapezoidal, parabolic, and the like). The lenticular lens is generally selected to accommodate both the interlaced image and the distance from which the image will ordinarily be viewed. Various types of lenses are commercially available.
A lenticular image comprises an interlaced precursor image that is joined to a lenticular lens in any of a variety of alternative ways (described further below). The preparation of an interlaced image is well known in the art. The interlaced image is a composite of two or more component images that are themselves preferably of photographic quality. The component images are selected based upon the desired features of the lenticular or final image (e.g., one or more of the following: zoom, flip, morph, motion). Component images are then arranged, segmented, interlaced and mapped to create the precursor image so that the precursor image corresponds with the lenticular lens to which it will be joined. In order to impart the illusion of depth and/or motion, the interlaced image is made from more than one picture or frame. Typically, four pictures are interlaced with one another in any desired sequence to form a composite image or picture that when viewed through the lenticular lens, imparts the illusion of depth and/or motion to the viewer. In order to impart the illusion of depth and/or motion to the viewer, the interlaced image must be “in phase”, or correspond with, the lenticules of the lens.
The interlaced image is typically printed to the flat back surface of the lenticular lens sheet or web. However, it is not uncommon to first print the interlaced image to a substrate (e.g., paper, plastic, metal, glass or wood) and then join, for example using an adhesive, the substrate bearing the image to the lenticular lens (i.e., thereby creating the lenticular image).
Today, lenticular technology is in use on a variety of items, such as: promotional buttons, magnets, coasters, collectibles, display posters, signs, menu boards, postcards and business cards. Lenticular technology is also used in packaging, publishing and labeling applications.
Lenticular lens material can be extruded, cast or embossed. The manufacture of lenticular lens material is a highly specialized process that typically involves the use of a precisely made lenticular pattern-forming device (e.g., an engraved cylinder or pattern roll). The device includes a groove pattern on its outer surface and this groove pattern is utilized to impart a lenticular profile (i.e., the array of lenticules or lenses). For example, when a plastic material (in the form of, for example, a sheet, web or film) is pressed against the groove pattern, the plurality of lenticules, which make up a lenticular pattern, are formed on a surface of the plastic material. In this way, a lenticular pattern is formed in the sheet or web that corresponds to the groove pattern.
More specifically, when the pattern-forming device includes grooves that are oriented to be parallel to its central longitudinal axis, the resultant lenticular lens material includes lenticules that run transverse to the length-wise direction of the lens material as it passes the device, and thus, such a pattern-forming device can be referred to as a “transverse pattern-forming device”. When lenticular lens product is manufactured in this fashion, printing and finishing operations (e.g., cutting, laminating, etc.) can be achieved or accommodated in-line with the manufacture of the lens web. Moreover, various end-use applications of the lens (e.g., lenticular image labeling) can be facilitated using lenticular lens manufacturing in web format, and in particular, lenticular lens made using a transverse pattern-forming device. Application Ser. No. 10/340,075, which is incorporated herein by reference, describes one such lenticular lens pattern-forming device for producing a lenticular lens web.
U.S. Pat. No. 6,596,361 to Klein teaches a process for forming lenticular labels on a continuous web so that the lenticules are perpendicular to the longitudinal axis of the web. The process includes the steps of: advancing a continuous web of label stock including an adhesive on both sides; providing multiple sheets of lenticular assemblies; and securing the sheets of lenticular assemblies to one side of the continuous web with the lenticules of the lenticular assemblies oriented perpendicularly to the length of the continuous web. One disadvantage associated with the teachings of Klein is that the method requires labels to be “on-serted”, or placed on to, a web of label material so as to achieve the ultimate desired orientation of the lenticular image label. In effect, an additional layer of material (i.e., the web of label material) is required to create a desired lenticular image label.
Accordingly, it would be desirable to provide a continuous lenticular image label web, as well as a method of manufacturing the continuous lenticular image label web. It would be desirable to create individual or discrete lenticular image labels out of the continuous lenticular image label web. The continuous lenticular image label web could advantageously be created in-line with printing and other operations consistent with web-lenticular format. The overall construction of the continuous lenticular image label web, as well as its resultant lenticular image labels, could be simplified. For example, it would be desirable to eliminate various layers (e.g., adhesive layers, or a label carrier layer), for example by eliminating the need for on-serting, so as to reduce the cost and time to manufacture the lenticular image labels.